• The Korean Journal of Applied Statistics
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• v.21 no.2
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• pp.247-264
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• 2008

This paper considers the integrated process control procedure for detecting special causes in an ARIMA(0,1,1) process that is being adjusted automatically after each observation using a minimum mean squared error adjustment policy. It is assumed that a special cause can change the process mean and the process variance. We derive expressions for the process deviation from target for a variety of different process parameter changes, and introduce a control chart, based on the generalized likelihood ratio, for detecting special causes. We also propose the integrated process control scheme bases on the future loss. The future loss denotes the cost that will be incurred in a process remaining interval from a true out-of-control signal.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.723-729
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• 2005

Traditional statistical process control(SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control(EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted variable sampling interval(VSI) to change sampling intervals in a predetermined fashion on the predicted process levels for integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA(1,1) disturbance model and zero-order (responsive) dynamic system. The properties of twelve control rules under three patterns of process change(sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• Journal of KIBIM
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• v.8 no.2
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• pp.10-18
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• 2018

BIM technologies store, share and integrate the information produced in each sector of the construction industry. From this point on, it increases the efficiency of the work. Currently, quantity take-off and process schedule are derived separately based on BIM technology. When calculating the quantity by process, relevant information shall be collected, reinterpreted, and reevaluated as required by the practice. The purpose of this study is to develop an integrated process and quantity management system through BIM collaboration and to build prototypes for steel structures. The main research is to build a construction BIM model for steel structures and a process BIM model through BIM collaboration. Furthermore, necessary information was selected and processed according to the user's needs for integrated management. Relevant integration outcomes are visualized graphically to maximize utilization. Through these studies, a system for integrated control of processes and supplies is provided, and the results are expected to contribute to the improvement of working efficiency and are easily and quickly reflected in design change and process change. In this study, we intended to enhance the usability of information by linking process schedules with quantity calculations based on BIM. Thus, the process for integrated control of the quantity of structural components by process unit and the BIM based schedule information was established. In addition, the efficiency of the information link of the integrated management system was considered for design changes and process schedule changes.

• Communications for Statistical Applications and Methods
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• v.7 no.2
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• pp.435-446
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• 2000

Statistical process control(SPC) and engineering process control(EPC) are two strategies for quality improvement that have been developed independently. EPC seeks to minimize variability by adjusting compensatory variables in order to make the process level close to the target, while SPC seeks to reduce variability by monitoring and eliminating causes of variation. One purpose of this paper is to propose the IMA(0,1,1) model as the in-control process model. For the out-of-control process model we consider two cases; one is the case with a step shift in the level, and the other is the case with a change in the nonstationarity. Another purpose is to suggest the use of an integrated process control procedure with adjustment and monitoring, which can consider the proposed process model effectively. An integrated control procedure will improve the process control activity significantly for cases of the proposed model, when compared to the procedure of using either EPC or SPC, since EPC will keep the process close to the target and SPC will eliminate special causes.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.3
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• pp.210-218
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• 2006

Traditional statistical process control (SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control (EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted by variable sampling interval (VSI) to change sampling intervals in a predetermined fashion on the predicted process levels under integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA (1,1) disturbance model and zero-order (responsive) dynamic system. Properties of twelve control rules under three patterns of process change (sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• Journal of Environmental Science International
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• v.29 no.5
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• pp.559-573
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• 2020

The purpose of this study analyzed the overview of corrugated cardboasrd manufacturing industry and then provide direction for improvement. The BREF (BAT reference document) is an important reference for licensees and officer, including the best available techniques for the industry and achievable environmental performance, technical characteristics, and economic information. In the corrugated cardboard manufacturing process, wastewater pollutants are generated throughout the production process, and water is used in the dissociation and aging process. Atmospheric emissions are mostly generated by steam production from boilers and incinerators for the dry process. SO₂, NOx, CO₂, CO, HCl, dust, VOC, and odor were common. In the EU-BREF (European union BAT reference documents) BAT for wastewater have taken up a relatively large proportion. Items of water pollutants in wastewater were common in COD, BOD, N, P, SS, and however EU-BREF had different pollutants such as AOX and salt compared to K-BREF. In order to improve the quality of the K-BREF, it is necessary to devise basic data research method and data acqusitiom method. Consideration should be given to additional environmental management techniques that reflect the emissions characteristics of the corrugated cardboard manufacturing process. In addition, further research is needed to develop methodologies for selecting BATs considering environmental and economic feasibility.

• Journal of Power Electronics
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• v.16 no.6
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• pp.2327-2337
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• 2016

The mode-switching control of transient process is important to grid-connected 400 Hz solid-state power supply systems. Therefore, this paper analyzes the principle of on-grid and islanding operation of the system with or without local loads in the grid-connected process and provides a theoretical study of the effect of different switching sequences on the mode-switching transient process. The conclusion is that the mode switch (MS) must be turned on before the solid-state switch (STS) in the on-grid process and that STS must be turned off before the MS in the off-grid process. A strategy of mode-switching smooth control for transient process of the system is proposed, including its concrete steps. The strategy utilizes the average distribution of peak currents and the smooth adjustment of peak currents and phases to achieve a no-shock grid connection. The simulation and experimental results show that the theoretical analysis is correct and that the method is effective.

• Journal of the Korean Data and Information Science Society
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• v.22 no.4
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• pp.679-690
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• 2011

Two widely used approaches for improving the quality of the output of a process are statistical process control (SPC) and automatic process control (APC). In recent hybrid processes that combine aspects of the process and parts industries, process variations due to both the inherent wandering and special causes occur commonly, and thus simultaneous application of APC and SPC schemes is needed to effectively keep such processes close to target. The simultaneous implementation of APC and SPC schemes is called integrated process control (IPC). In the IPC procedure, the output variables are monitored during the process where adjustments are repeatedly done by its controller. For monitoring the APC-controlled process, control charts can be generally applied to the output variable. However, as an alternative, some authors suggested that monitoring the input variable may improve the chance of detection. In this paper, we evaluate the performance of several monitoring statistics, such as the output variable, the input variable, and the difference variable, for efficiently monitoring the APC-controlled process when we assume IMA(1,1) noise model with a minimum mean squared error adjustment policy.

• Korean Journal of Child Studies
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• v.31 no.1
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• pp.283-300
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• 2010

This paper investigated the effect of music and science integrated activities using instruments designed to test both musical concept and science inquiry process skills of children. The subjects of this study consisted of two classes of children aged 5 at H Kindergarten in Busan city. This study involved a class of 31 children using a music and science integrated curriculum as the experimental group and another class of 32 children using a traditional music and science curriculum as the control group. The integrated activities were used 12 times over a 6-week period. A test was taken to evaluate the effects of the integrated activities on the children's understanding on seven sub-categories of musical concepts and six sub-categories of science inquiry process skills. The results were that the experimental group showed significantly higher improvements in all subcategories of musical concept and science inquiry process skills, compared to the control group. Based on these results, we concluded that these integrated activities were effective in the development of both musical concepts and the science inquiry process skills of children.

• Communications for Statistical Applications and Methods
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• v.17 no.3
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• pp.357-365
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• 2010

This paper considers the integrated process control procedure for detecting special causes in an IMA(1,1) noise process that is being adjusted using a minimum mean squared error adjustment. As a SPC procedure, we use a GLR chart for detecting special causes whose effects are the sustained shift or the sustained drift in the process mean, and the sustained shift in the process variance. For the design of the GLR chart, we derive expressions for the control limit which accurately satisfies the given in-control ARL.